# https://leetcode.cn/problems/contains-duplicate/description/?envType=problem-list-v2&envId=array
from typing import List


class Solution:
    def containsDuplicate(self, nums: List[int]) -> bool:
        if len(set(nums)) == len(nums):
            return False
        if len(set(nums)) != len(nums):
            return True


if __name__ == '__main__':
    s = Solution()
    print(s.containsDuplicate([1, 2, 3]))
